Case Studies
Extend Life of BWE Cylinders
Challenge
Issue
A continuous surface lignite mine was facing issues with boom lowering hydraulic cylinders of compact type bucket-wheel excavator. Only a few years into operation, the cylinders were experiencing continuous leakage and malfunction (piston seal by-pass).
The large diameter cylinders were exposed to heavy payload, shock load, pressure peaks, and deflection by long stroke and angle position.

Compact lignite bucket-wheel excavator.
Solution
Recommendation
The Chesterton team developed a seal system that was installed during a planned overhaul.
The sealing solution included Chesterton® 5K Wiper, 10K Rod Seal, 10K Piston Seals, and replaceable 19K Bearing Bands. A combination of innovative sealing materials was used:
- AWC800 proprietary polymer: Best-in class sealing technology with high wear and abrasion and extrusion resistance.
- AWC660: A high loading capacity, engineered plastic with built-in lubricants that prevent metal-to-metal scoring and prolong equipment life.

Bucket-wheel boom lowering cylinders in operation.
Results
Improved cylinder performance and reliability
- The end-user was extremely satisfied with the performance.
- Extending the hours of operation between maintenance intervals and increasing the overall asset life.
- Environmental concerns were eliminated by leak-free operation of the rod seal system.
- The high-performance piston seal system reduced the possibility of cylinder malfunction.

Boom lowering cylinders in repair shop.